Sample of a Table from actual greatfeet.com stats:

Day of 12/14/2003: Screen Resolution

Screen Resolution

Computers offering at least 640x480 pixels, but less than 800x600 pixels, are reported as 640x480, and so on.

#
 Resolution
 Computers
 %
1
 640x480
     7,217
   2.36
2
 800x600
 121,662 39.82
3
 1024x768
 152,696 49.98
4
 1280x1024
   20,788   6.80
5
 1600x1200
     3,147   1.03